Early photos of Zuckerberg show him in a plain T-shirt, sweats, and Adidas sandals lounging on the steps of his would-be alma mater. Although Zuckerberg's wardrobe hasn't changed much (albeit the slides and sweats), the company he founded has.

However, for the last few years, Facebook has faced scandal after scandal. It's been called out on multiple occasions for the way it handles user data. Zuckerberg testified for 10 hours in front of Congress last April over the Cambridge Analytica data-harvesting scandal.

Facebook has also been the center of debates regarding how to regulate when tech companies that have too much power.

Steve Jobs and Steve Wozniak started Apple Computer Company in 1976 in Jobs' garage. Jobs was just 21.

Steve Jobs at the first West Coast Computer Faire in San Francisco, California, April 1977.
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Jobs famously left (or was ousted, depending on who you believe) in 1985, after clashing with CEO John Sculley. Twelve years later, Apple bought Jobs' startup NeXT Computer, bringing him back into the fold.

Jobs ushered in a new era at Apple, introducing the iPhone and iPad. In 2003, he was diagnosed with a unique form of pancreatic cancer.

Bill Gates and Paul Allen founded Microsoft in 1975. Gates was just 20 years old, and like Zuckerberg, he dropped out of Harvard to spend more time with his technology startup.

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Gates and Allen met in high school, when both were obsessed with computers and software. They built Microsoft from a company that just designed and sold software, into one that sells its own consumer electronics, operating suites, and personal computers.

Google, the catalog of "every link on the internet," is now the world's most-used search engine. The company has also branched out significantly: It spans video content, mobile technology, education, digital libraries, and even self-driving cars.

Page, now 46, is the seventh-richest person in the world with a net worth of $65.4 billion. In December 2019, he stepped down as CEO of Alphabet, Google's parent company.

Tesla's "autopilot" system is available on all three of its models, including the new Model 3 — a lower-cost car launched in early 2017 that brings the company closer to its goal of making electric vehicles that are affordable for the masses.